Candida albicans is a diploid yeast that, under certain conditions, can cause oral or oropharyngeal infections, particularly in immunocompromised individuals. Recent molecular investigations have classified genotypes A, B, and C for Candida albicans, along with genotype D for Candida dubliniensis. This study aimed to identify the different genotypes of the C. albicans complex in drug abusers in Iran. Oral swabs were collected from drug abusers and cultured on CHROMagar Candida. A 21-plex PCR method was employed for the detection of isolates, and the Candida 25S rDNA gene was amplified using primer pairs CA-INT-L and CA-INT-R for ABC genotyping of C. albicans. Out of the 245 substance abusers screened, 151 individuals (61.63 %) were found to harbor the C. albicans complex. The most common genotype among patients was genotype D (39.1 %), followed by genotype A (31.12 %), genotype B (9.93 %), and genotype C (5.29 %). Additionally, 14.56 % of patients had a mixed genotype. Notably, significant differences in genotype distribution were observed in relation to age, underlying diseases, and marital status (P < 0.05). This study highlights the significance of molecular genotyping in understanding the epidemiology of C. albicans and C. dubliniensis in at-risk groups.